Impact of the Phaeocystis globosa spring bloom on the intertidal benthic compartment in the eastern English Channel: a synthesis.
From 1999 to 2005, studies carried out in the frame of regional and national French programs aimed to determine whether the Phaeocystis globosa bloom affected the intertidal benthic communities of the French coast of the eastern English Channel in terms of composition and/or functioning. Study sites were chosen to cover most of the typical shore types encountered on this coast (a rocky shore, an exposed sandy beach and a small estuary). Both the presence of active Phaeocystis cells and their degradation product (foam) did have a significant impact on the studied shores. The primary production and growth rates of the kelp Saccharina latissima decreased during the bloom because of a shortage of light and nutrient for the macroalgae. On sandy sediments, the benthic metabolism (community respiration and community primary production), as well as the nitrification rate, were enhanced during foam deposits, in relation with the presence of bacteria and active pelagic cells within the decaying colonies. In estuarine sediments, the most impressive impact was the formation of a crust at the sediment surface due to drying foam. This led to anoxic conditions in the surface sediment and resulted in a high mortality among the benthic community. Some organisms also tended to migrate upward and were then directly accessible to the higher trophic level represented by birds. Phaeocystis then created a shortcut in the estuarine trophic network. Most of these modifications lasted shortly and all the systems considered came back to their regular properties and activities a few weeks after the end of the bloom, except for the most impacted estuarine area.
Spilmont
Nicolas
N
Université des Sciences et Technologies de Lille, Laboratoire d'Océanologie et de Géosciences, CNRS UMR 8187 LOG, Station Marine de Wimereux, Wimereux, France. nicolas.spilmont@univ-lille1.fr
Denis
Lionel
L
Artigas
Luis Felipe
LF
Caloin
Frédéric
F
Courcot
Lucie
L
Créach
Anne
A
Desroy
Nicolas
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Gevaert
François
F
Hacquebart
Pascal
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Hubas
Cédric
C
Janquin
Marie-Andrée
MA
Lemoine
Yves
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Luczak
Christophe
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Migné
Aline
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Rauch
Mathieu
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Davoult
Dominique
D
D001493:Bathing Beaches; D017753:Ecosystem; D004739:England; D056890:Eukaryota / Q000254:growth & development / Q000502:physiology* / Q000648:ultrastructure; D005068:Eutrophication; D005602:France; D019015:Geologic Sediments / Q000737:chemistry; D044423:Kelp / Q000254:growth & development / Q000502:physiology; D008855:Microscopy, Electron, Scanning; D009792:Oceans and Seas; D010100:Oxygen / Q000378:metabolism; D010788:Photosynthesis / Q000502:physiology; D000644:Quaternary Ammonium Compounds / Q000378:metabolism
D000644:Quaternary Ammonium Compounds; D010100:Oxygen